Delivery of commercial fluids from fluid transportation vehicles is conventionally accomplished with hydraulic drive systems that include a hydraulic pump driven by a prime mover (e.g., an internal combustion engine) of the delivery vehicle, a hydraulic motor driven by the hydraulic pump, and a fluid delivery pump mechanically coupled to and driven by the hydraulic motor. The hydraulic pump converts torque from the prime mover into a flow of pressurized working fluid (e.g., hydraulic fluid), which is used to drive the hydraulic motor. Torque generated by the hydraulic motor in response to the flow of pressurized hydraulic fluid delivered by the hydraulic pump rotates the fluid delivery pump, which offloads the commercial fluid from the vehicle.
The hydraulic pump and hydraulic motor may be located remote from one another and may be connected through fluid lines. For example, the hydraulic pump may be located on a tractor portion of a tractor-trailer and driven by a power take-off (PTO) of the tractor's drivetrain, while the hydraulic motor and fluid delivery pump may be located on the trailer portion. Such drive systems may include various other hydraulic componentry such as control valves, fluid reservoirs, fluid coolers, etc.
A need exists to improve such fluid delivery systems. For example, it is desirable to reduce weight and complexity of such fluid delivery systems and the associated hydraulic drive systems.